Integrated circuits processes electrical signals to produce rich electronic applications. One dominant type of devices making up these integrated circuits is the metal-oxide semiconductor (MOS) devices. Technology advances have allowed MOS devices to be produced using deep nanometer complementary metal-oxide semiconductor (CMOS) processes, for example 65 nanometer (nm) nodes and smaller. While these devices allow many integrated circuits to become more compact, faster, and/or more powerful, these devices can suffer from so-called “aging effects”. In simple terms, over time, during active operation, aging's net effect is that the MOS devices' characteristics experience individual parametric drifts depending on their operating conditions including their quiescent point, their large signal operation, and the their temperature. Different devices can age in different amounts depending on the individual operating conditions within the same die or even the same circuit.
“Aging Degradation and Countermeasures in Deep-submicrometer Analog and Mixed Signal Integrated Circuits” by Shailesh More (Apr. 30, 2012) and “Device Aging in Analog Circuits for Nanoelectronic CMOS Technologies” by Florian Raoul Chouard (Apr. 25, 2012) were two doctorate dissertations which examined aging degradation effects in analog and mixed signal circuits. The authors discussed countermeasures such as chopper stabilization, auto-zeroing techniques, and calibration techniques to address aging of devices.